Yeah, actually, there are two ways to do it:
The first is you can use a mediacenter plugin like SecondRunTV: http://www.secondrun.tv/
Setup your BBC/ITV.. I also setup several other channels, and then have them mapped to go through the proxy. That way, the proxy ONLY kicks in when you are watching content from those sources, saving you the headache above.
The other method is to use PlayOn: http://www.playon.tv/playon and a linking product, TubeCentric. http://tubecentric.tv/
The two together can also be made to parse, arrange, and download for viewing shows straight from ITV/BBC. It's good stuff. BBC has upgraded almost all of it's streams to 720P, basically.. and it looks decent. Not as good as US broadcast, but definitely a step up from SD. And, you can use schedulers and other tools to make sure you have to ready to watch when you want.
The world is getting much closer - even for those of us who do it "legit". :)